DE1425008C - Hollow screw for arrangements made up of constant helix screws - Google Patents

Description

1 sheet of drawings

Claims (1)

1 2 The present invention is based on a The two known hollow worms each rotating in the same direction around a worm axis for parallel arrangements touching each other exactly in each from mutually exactly scraping co-twist position, since the screws seen in cross section, which are made of sheet metal, in particular without cutting is made at any point from a piece of pipe eccentric to the axis. There are 5 circles with R = 0.5 A, which touch each other in each position. Thus, a screw machine scrapes each other off for kneading, gelatinizing with an eccentric circular cross-section and pre-pressing of plastic masses known. You get several worm shafts with constant twist detes thread on the outside and inside. It is thus achieved that the turn off, the thread groove made by the engaging sheet metal does not have any sharp crests of the counter-worm on the flank edges or tips, so that completely or almost completely sheet metal deformation for a chip contact point for the production of dig is sealed along a space curve. Hollow screw particularly favorable conditions spirit the flank profile in such a way that the flanks are created without having to forego the exact engagement of the surface in its intersection with any flat screw flights and flights.
Surfaces perpendicular to the screw axis circular arc. In a drawing, an exemplary embodiment is now obtained, which have the radius r = center distance of the play of the hollow screw according to the invention purely two screw shafts and the Kernra- shown schematically and touching the earth radius of the screw shaft in more detail below. This purifies; namely shows twist snails are cut from solid. There 20 Fig. 1 a longitudinal section through two interlocking However, there is a desire to also use such co-rotating co-twist worms 2 and 3 and twist screws as hollow screws made of sheet metal to form Fig. 2 a cross section through the co-twist men to reduce manufacturing costs. screws according to line xy in A b b. 1. Hollow screws made of sheet metal are already known, the co-twist screws are loaded with 1 and 2 as for example the German patent specification 25 draws its associated axes with 3 and 4 1053 883 shows. Here is a screw spindle (Fig. 1) and the cross-sectional profile (eccentric wrote that from a hollow sheet metal body circle) the hollow screw 1 with 5 (Fig. 2). the consists of pressed sheet metal parts in the form of a diameter of the eccentric circle 5 U-profile strip is made, the base web of the center distance A (Fig. 2) of two merging a sector of a 3 ° kender hollow screw 1 and 2 having the spindle diameter. The construction of the worm thread with the thread corresponding to the helical toothing is pressed into it, the pitch // (Fig. 1) is created by removing the pressed sheet metal parts on their four radial paths aa shown in Fig. 2 ' Long sides lying with one another or bb' or cc or dd! are welded on four in parallel. Such screw spindles are intended for 35 ^{tools at a distance of 1} Zn of the pitch // to each other and their manufacturing process, drawn straight lines I, II, III and IV (Fig. 1), cannot be used for the manufacture of hollow worms outer diameter radially inward. The constructive turns, which are countered as co-twisting screws, become more precise the more straight lines are to be scraped off on the side. A b b. 1 or sectors in the A b b. 2 co-spiral screws with a cross-section of 40 are selected. From the straight line IV onwards, the shape of the screw profiles continues in a mirror-inverted manner up to point 0, etc.
Patent specification 862 668 for diameters of over The proportions of the diameter (outer diameter about 200 mm as a hollow body made of sheet metal, knife: core diameter), the center distances and thus result from the geometrically determined sharp slopes are free or angular shape of the thread in the case of the thread described Production 45 selectable and no geometric limits ge-deformation difficulties. bundle. Since these deformation difficulties are not patent claim
can be remedied, the invention has the task made to create a thread form that ensures the desired mutual 50 mutually exactly scraping co-twist scraping with hollow screws for parallel arrangements of co-twist screws and on the other hand also worm, which poses no difficulties from sheet metal, in particular without cutting, positionally. from a piece of pipe, characterized in that this object is achieved in that each arbitrary transverse cross-section of the hollow screw is a cut to the axis of the hollow screw (1, 2) is a circle eccentric to the axis, the diameter of which is 55 (3, 4) is an eccentric circle (5) whose center-to-center distance of two cooperating hollow blades corresponds to the center distance (A) of two co-worms. acting hollow screw corresponds.